The dwindling supply of labor has resulted in substantial attention being directed to the harvesting of trees by mechanical means. One of the more popular machines that is presently being utilized for this purpose is a feller-buncher which generally consists of a head that is mounted on the end of a conventional boom and dipper stick assembly which is pivotally supported on a turntable of a vehicle. The feller head includes grapple means for grasping a tree and cutter means for severing the tree adjacent the ground.
In order to increase the versatility of these machines and, therefore, the productivity thereof, some felling heads are capable of cutting and retaining a plurality of trees prior to depositing them on the ground. For example, the above-mentioned Tucek patent discloses a single accumulator arm that cooperates with vertically spaced fixed tree engaging elements on the support and the accumulator arm is pivoted on the support between first and second positions. The accumulator arm consists of first and second portions that are pivotally interconnected between adjacent ends thereof and are normally biased to an end-to-end position by biasing means normally maintaining the portions of the accumulator arm in end-to-end position while accommodating pivotal movement relative to each other. While such an accumulator device has been found to perform the required function of collecting trees, the overall size of the biasing mechanism and the degree of difficulty of assembling the unit have resulted in substantial cost for such an assembly.